Lenovo System x3550 M4 Installation And Service Manual page 264

Statement 34
CAUTION:
To reduce the risk of electric shock or energy hazards:
• This equipment must be installed by trained service personnel in a restricted-access location, as
defined by the NEC and IEC 60950-1, First Edition, The Standard for Safety of Information
Technology Equipment.
• Connect the equipment to a properly grounded safety extra low voltage (SELV) source. A SELV
source is a secondary circuit that is designed so that normal and single fault conditions do not
cause the voltages to exceed a safe level (60 V direct current).
• Incorporate a readily available approved and rated disconnect device in the field wiring.
• See the specifications in the product documentation for the required circuit-breaker rating for
branch circuit overcurrent protection.
• Use copper wire conductors only. See the specifications in the product documentation for the
required wire size.
• See the specifications in the product documentation for the required torque values for the wiring-
terminal screws.
Important: Be sure to read the multilingual safety instructions on the CD that comes with the server before
you use the product.
To remove a hot-swap dc power supply, complete the following steps:
Step 1. Read the safety information that begins on "Safety" on page v and "Installation guidelines" on page
31.
Step 2. If only one power supply is installed, turn off the server and peripheral devices and disconnect all
power cords.
Step 3. If the server is in a rack, at the back of the server, pull back the cable management arm to gain
access to the rear of the server and the power supply.
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Lenovo System x3550 M4 Installation and Service Guide